Tastes are measured in various situations, such as encountered in the food industry, clinical sites and others. Up to now, most of the taste measurements are carried out as taste tests relying on human gustation. However, due to the judgments being made by humans, the results vary depending on the individual human taster. The influences of the physical and psychological conditions of the human tasters, as well as blunting of the sense of taste in case of continuous measurements, cannot be ignored. Thus, a taste sensor, which can quantify the tastes sensed by humans more objectively and free from the above-mentioned influences is required.
In order for a taste sensor to simulate the human gustation system, it is not sufficient that the taste sensor can classify and identify the samples, but it is additionally required that the taste sensor can quantify the intensities of the tastes which humans actually sense. To achieve a taste sensor, the sensor is required to have a correlation with human gustation, and to be able to qualitatively and quantitatively analyze the tastes (Non-patent Literature 1). Toko et al. developed a taste sensor which quantifies the tastes of samples (Non-patent Literature 2) This multi-channel taste sensor comprises electrodes having a lipid/polymer membrane, and creates different response patterns for chemical substances having different tastes. The output signals are quantitative.    Patent Literature 1: WO 03/044498 A1    Non-patent Literature 1: Legin, A.; Rudnitskaya, A.; Lvova, L.; Vlasov, Y.; Natale, C. D.; D'Amico, A. Anal. Chim. Acta 2003, 484, 33-44.    Non-patent Literature 2: Toko, K. Meas. Sci. Technol. 1998, 9, 1919-1936.    Non-patent Literature 3: Meng Joo et al., IEEE Transactions on Neural Networks, vol. 13, N03, pp 697-710, MAY 2002    Non-patent Literature 4: S. A. Billing et al., Mechanical Systems and Signal Processing, Vol 13(2), pp. 335-349, 1999    Non-patent Literature 5: Keun Burn Kim et al., Information Sciences, vol. 130, p165-183, 2000    Non-patent Literature 6: M. Marinaro et al, Neural Networks, vol. 13, pp. 719-729, 2000    Non-patent Literature 7: S. Alberecht, Neural Networks, vol. 13, pp. 1075-1093, 2000    Non-patent Literature 8: Masatoshi SAKAWA et al., “Introduction to Neuro Computing” Morikita Publishing Co., Ltd., 1999